1. Field of the Invention
The invention relates to the field of fillers for containers carried axially upright on a conveyor in an X-Y array, and more particularly to a filler arranged for at least semiautomatic job changing from containers of one dimension to containers of another dimension. A plurality of individual nozzles in the array are re-positionable in the array such that when containers having a larger or smaller lateral dimension are to be run, the individual nozzles are movable into registry with the new array.
2. Prior Art
Filling machines for containers such as beverage bottles and the like conventionally pass the containers in a single file along a conveying path, with the containers opening axially upwardly for filling via nozzles that direct fluid or other material contents downwardly into the containers. High speed filling lines may have a rotary carousel with a number of filling nozzles guided by a cam. The carousel rotates to move the nozzles synchronously with the passing containers and the cam moves the nozzles downwardly to engage against the containers. Contact with a container causes the filler to discharge, for example via a valve in the respective nozzle opened by axial pressure with the end of the container or a neck of the container. U.S. Pat. No. 4,493,349--Pomponio, Sr. discloses a valve arrangement as described.
It is possible that a plurality of nozzles in a serial line filling machine may operate simultaneously to fill a number of adjacent containers in the stream, either by moving synchronously with the containers or by arranging for a group of containers to be stopped while they are filled. It is also possible that two serial lines of containers may be served by adjacent rows of filling nozzles. U.S. Pat. No. 3,651,836--Johnson discloses a filling machine that serves two parallel streams of containers using banks of four adjacent nozzles to serve four adjacent containers in each stream. Another example of a filler that fills a group of containers simultaneously is shown in U.S. Pat. No. 3,020,939--Donofrio.
It is necessary in a filling machine having spaced nozzles to ensure that the nozzles align in registry with the containers they are to fill. In a serial filling line, the sidewalls or rails of a conveyor, slide track or similar arrangement typically guide the bottles along the conveyor and prevent the containers from being displaced laterally of the direction of advance along the container stream. The sidewalls, rails or the like keep the centerlines of the containers along the centerline of the row of nozzles.
For linear positioning along the direction of advance, either each container is abutted directly against the longitudinally preceding and following container, or container-carrying pockets are provided at a fixed spacing, to ensure that the containers (and specifically the open tops of the containers) are at the same linear spacing as the nozzles. In Donofrio, the containers are urged laterally against a container sidewall and stopped longitudinally by a movable stop that obstructs the container path and thereby holds the containers in place while they are filled. A filler of this type, which handles groups of containers, can operate "continuously" by filling a first group and then the next adjacent group in a periodic cyclic motion. Typically the filling motion is simply an axial advance and retraction of one of the nozzles and the containers relative to the other, for discharging contents through the nozzles.
It could speed the filling of containers further if an entire X-Y array of containers is filled simultaneously. However, there are problems in adapting such an arrangement to high speed or continuous operation because of problems in ensuring that the containers in the array are in registry with the nozzles. As a result, gang filling tends to be much more of a batch operation than a continuous one.
Examples of gang filling an array of containers are disclosed in U.S. Pat. Nos. 4,055,202--Greene; 4,270,584--van Lieshout; and 4,411,295--Nutter. In each case a regular X-Y array of containers is provided that corresponds to an array of nozzles or fill heads. In Greene the containers are bottles; in van Lieshout they are open top cups for beer; and in Nutter the containers are 55 gallon drums having off-center fill holes.
In order to maintain array positions, Green holds the bottles in a box in which the bottles f it so closely as to occupy regular positions in mutually perpendicular directions when the box is full. If such a box is not entirely full the container positions are uncertain because the abutment of the containers is relied upon to position them. A similar situation could be obtained by defining receptacles for the containers, e.g., by webbing forming crossing walls between the outer walls of the box. The bottles must be moved axially into such receptacles or into the spaces between other bottles, suggesting a manual operation. In van Lieshout, beer cups are placed manually into a box nearby one another but spaced somewhat. The open tops of the cups provide a wide enough target for the nozzles that spacing is not critical, provided the cups are substantially regularly spaced, i.e., by a manual operation. In van Lieshout, one row is filled at a time. In Nutter, not only must the 55 gallon drums be in correct position, but additionally their fill openings must be turned to toward one another in groups of four, for aligning with a fill head having four discharge fittings. Manual attention to positioning is required.
Each of the foregoing gang filling arrangements requires manual attention to set the containers in position, and is not as suited to automation as the serial fillers mentioned above. Although it is helpful in Greene and van Lieshout that the containers are boxed as a part of this process, and can thereafter be handled as a unit, there is no practical way to position and fill a "bulk" group of containers automatically or semiautomatically by these methods.
In each of these prior art gang filling machines, the nozzles are fixed in position. For example in Greene, a tank is subdivided for measuring the amount to be discharged into each container and the valves comprise fixed structures coupled to the tank at the centerline of each receptacle. In van Lieshout, taps are fixed at the required positions along an arm disposed over the array, the fixed positions corresponding to the pitch of the container spacing. In order to use such a machine to fill containers of some other size, most or all of the filling structure would have to be replaced. Although soft drinks and beer may involve runs of a large number of bottles, if a relatively small number of containers are to be filled in a production run (e.g., as typical of liquor), rebuilding the filling machine or providing an additional filling machine are not cost justified.
Lightweight containers present special problems when one attempts to handle them in bulk. Containers such as polyethylene terephthalate or "PET" are inexpensive and durable, and the minimal weight of the material makes it attractive for shipping and handling. However, the containers very easily fall over when unsupported by adjacent containers and/or as a conveyor structure. Line operation speeds of linear filling lines must be slower than comparable filling lines running heavier, more stable glass containers. When handled in bulk, containers are prone to define an array with voids, and for PET containers the voids cause containers to fall over, requiring manual attention.
Bulk containers can be nested in a regular array by laterally inward pressure on the group. By engaging the outermost rows of containers in an array using a scaled bar, as disclosed in copending application Ser. No. 07/957,413, filed Oct. 5, 1992 and entitled CONTAINER FILLER, ESPECIALLY FOR BALLAST, HAVING CONTOURED SWEEP FOR ARRAYING CONTAINERS, which is hereby fully incorporated by reference, it is possible to use the shape of the outermost containers to engage the inner containers in a similar fashion, forcing all the containers to assume positions in a regular array. For containers having a round cross section, adjacent rows or columns are staggered. For other cross sections, other arrays are possible.
Whether the containers are arranged in bulk or in regularly spaced receptacles of one kind or another, a minimum spacing between the centerlines of the containers is defined by the lateral size of the containers. The filling openings of larger sized containers are necessarily spaced by a greater minimum distance than the filling openings of smaller containers. Although it would be possible to build a gang filling machine with nozzles aligned to the largest possible containers, running smaller containers on the filling machine would require substantial steps to ensure that the smaller containers are presented in registry with the filling nozzles. This would waste packing and processing space (e.g., in receptacle carrier boxes) or would require some additional means to position the individual containers at the correct distance along two mutually perpendicular axes. When conducting a job change, new (narrower) conveyor structures would be needed. Although this could be accomplished, the change would be most cumbersome. The conveyor guides could be brought closer together and a new understructure having means to linearly space the containers would be needed.
Conversely, one could provide a gang filling machine having nozzles arranged for the smallest containers arranged in the most densely packed possible array, and then only use those nozzles which align with the openings of larger containers. Whereas the nozzles typically do not discharge unless they contact a container, such an arrangement would be possible with careful planning of the various sizes of containers to be run. More particularly, larger containers would need to be wider than smaller ones by a planned amount (e.g., in multiples of uneven numbers), so that the centerlines of the larger containers would fall at the same points as smaller ones. This solution to the problem is also cumbersome, as well as expensive because many of the nozzles would routinely go unused.
A gang filling machine is needed that more efficiently solves the problems of providing a regular array of containers that corresponds to a regular array of nozzles, and can be quickly and conveniently set up to run containers of varying sizes.